Embalming was developed and widely practised in ancient Egypt where, from around 6000 BC to 600 AD, as many as 400 million bodies are thought to have been mummified. The processes involved in traditional Egyptian embalming have led to the remarkable preservation of many bodies.
In more modern times in the USA, it was normal for bodies to be preserved by packing them in ice, a practice only changed at the time of the Civil War when national war cemeteries were established and the practice of arterial embalming became widespread for bodies to be transported to these cemeteries. Arterial embalming had become established in the United Kingdom in the 18th century when bodies were first held for viewing. Demand grew and embalming became more established in the United Kingdom and particularly in the USA because of the distances involved in transporting bodies home.
The earliest modern embalming fluids contained arsenic but these fluids were soon replaced by formaldehyde based embalming fluids. Despite its unpleasant and dangerous properties, the use of formaldehyde in embalming has become almost universal.
Formaldehyde has long been used in the embalming profession as it confers excellent-preservative properties on the body and is an effective disinfectant and anti-microbial agent. Formaldehyde acts as a chemical fixing agent reacting with the soluble albumins (proteins) in the cells of the body and converting them to albuminoids, which are gels By pumping a formaldehyde solution through the vascular system of a body, the chemical agent perfuses into the tissues and exerts its disinfecting and preservative functions.
The modern embalming process involves flushing out the blood from the circulatory system of the body and replacing it with an embalming fluid which has a stabilising and protecting action on the body. The embalming fluid is injected into the arterial system of the cadaver and directly into some organs. Displaced body fluids are treated and disposed of via the public sewerage system or more usually by a contracted disposal firm.
The normal steps in the modern embalming process are as follows:                The body is placed in a proper position on the embalming table with the pubic area covered with a modesty cloth.        The body is washed and disinfected.        The face is shaved as necessary.        The eyes are closed. This is usually accomplished with a small curved plastic disc called an “eye cap” placed under the eyelid Perforations in the cap are sometimes present to help hold the eyelid in place.        The mouth is closed. This is usually accomplished by the placing of a specially designed “tack” in the upper and lower jaw. Each tack has a fine wire attached. By twisting the two wires together, the jaw is thus closed and the lips are set to the natural lip line using a cream to retain the proper position and to prevent dehydration.        The lower body orifice(s) may be plugged to prevent leakage.        The embalming solution is prepared. The modern embalming machine consists of a 2-3 gallon reservoir and an electric pump.        An incision is made over the carotid artery (where the neck meets the shoulder) or over the femoral artery (in the leg at the groin). The artery and a nearby vein are located and isolated.        A tube which is attached to the machine is inserted into the artery. A slightly larger tube is placed into the accompanying vein. This tube is attached via a hose to a collecting tank.        The fluid is injected into the artery under pressure by the embalming machine. As the blood is displaced by the fluid going in, it is forced out of the body from the vein and is disposed of. The pressure forces the embalming fluid into the capillaries and eventually to the cells of the body. After sufficient solution (typically approximately 2-10 liters depending on body size, more particularly vascular capacity) of solution are injected into the body, the blood has thinned the fluid coming through the vein tube is mostly embalming fluid.        The tubes are removed and the incision sutured.        The abdominal cavity is treated by the use of a hollow tube called a trocar that is used to aspirate gases and liquid contents under suction. A preservative chemical—and generally a more concentrated solution of the embalming fluid—is introduced via the trocar needle.        The body is again washed and cream is placed on the hands and face to prevent dehydration.        The hair is shampooed and the fingernails cleaned.        The body is covered with a sheet awaiting dressing and placement in the casket.        Cosmetics may be applied later to improve the natural colour of the body, although this will be less important if the embalming fluid includes a colorant. Much of the natural colour is created by blood in facial capillaries—this is no longer present after embalming. In the case of women, cosmetics used in life may also be used to recreate the “look” the person had during life. The hair is combed or set.        
Formaldehyde is obtained commercially as an aqueous solution (formalin), which is usually a ca. 28% solution, and this is diluted down by the embalmer to ca. 1-3% concentration. Typically, and depending on body size, more particularly vascular capacity, 2-10 liters of diluted solution are used per embalming. A more highly concentrated form of solution is usually used as a cavity fluid.
Formaldehyde based embalming fluids may or may not contain other chemicals such as: colorants to redden or tan the body and give it a more life-like appearance, emollients to keep the skin soft and sequestrants to chelate divalent cations present in some tap waters, which may cause undesirable performance of the embalming fluid. Other additive chemicals can be disinfectants, humectants and pH stabilisers.
Although, formaldehyde is very effective in preserving tissues for the timescale required, it is nevertheless a very hazardous material and subjects the user to significant health risks. Studies have indicated the formaldehyde is a potential human carcinogen and airborne concentrations of above 0.1 part per million (ppm) can cause irritation of the eyes, nose and throat. The severity of the irritation increases as concentrations increase; at 100 ppm it is a danger to life and health. It has been linked to many different forms of cancer, nasal, lung, testicular and brain cancer as well as leukaemia. Studies conducted by the National Cancer Institute in the USA have shown that embalmers were at greater risk for leukaemia, testicular and brain cancer than the general public.
Within the last twenty five years the use of formaldehyde in the workplace has become subject to regulation. The US Department of Labour, occupational Safety and Health Administration (OSHA) has placed increasingly stringent limits upon formaldehyde vapour exposure in the workplace. The permissible exposure limit (PEL) is 0.75 ppm measured as an 8 hour time weighted average, it also specifies a 2 ppm short term exposure limit, (i.e. the maximum exposure allowed during a 15 minute period). Even with careful practice embalmers are often subject to high doses of formaldehyde during the embalming process. It has been determined that embalmers are exposed to formaldehyde at concentrations averaging up to 9 ppm during embalming. This is significantly higher than the allowable limits.
In addition, the disposal of formaldehyde can create problems as it should not enter sewerage systems or water courses. Its effect on soil and soil organisms is not known but formaldehyde has been shown to be toxic to fish and related species when introduced into water systems. Recommended disposal is via incineration.
There is therefore a long term problem both for the environment and for the embalmer himself in using formaldehyde in embalming fluids. Consequently there is a need for an embalming fluid which is essentially free from formaldehyde.
The awareness of the dangers associated with repetitive exposure to formaldehyde has provided a stimulus for a search for alternative embalming fluids. One replacement for formaldehyde is glutaraldehyde and the use of glutaraldehyde in embalming fluids is described in U.S. Pat. Nos. 5,405,606 and 5,607,668.
There have been other patents relating to formaldehyde-free embalming compositions. For example, U.S. Pat. No. 3,983,252 discloses a stable dialdehyde-containing disinfectant for use in the medical field and household objects. The compositions are described in this patent as being useful in leather tanning, tissue fixation in electric microscopy, as protein reactants and as embalming fluids.
U.S. Pat. No. 4,675,327 discloses an anti-microbial compositions for embalming preparations comprising a combination of a disinfectant and a plant growth-regulating compound. Disclosed as disinfectants are a wide variety of anti-bacterial agents such as sulfonamides, penicillin, cephalosporin and bactracin, and salts thereof. Disclosed as skin disinfectants are alcohols, sources of active halogens, phenolics and their derivatives, salts such as sodium hypochlorite, aldehydes including formaldehyde, peracids and their derivatives and quarternary ammonium compounds. Metal binding agents which are disclosed include compounds which can be chelating compounds, sequestering compounds or dyes. Other disinfectants disclosed are heavy metal disinfectants such as mercury compounds, copper compounds, silver compounds and arsenic compounds.
U.S. Pat. No. 5,670,333 discloses formaldehyde-free tissue preservative compositions useful in the field of mortuary science and histology. Disclosed in this patent is an aqueous solution of ethanol, ethanedial, a long chain polymer and a polar aprotic solvent as an arterial injection fluid for use in preserving animal bodies. Also disclosed as a formaldehyde-free composition are aqueous solutions of ethandedial, a polar aprotic solvent, a proteolytic enzyme, a surfactant, an anti-microbial agent and optionally a chelating agent, which composition is for use as a pre-injection composition to cleanse the circulatory system in preparation for the administration of the inventive tissue preservative composition. In addition, this patent describes a formaldehyde-free body cavity fluid for use in an embalming process which comprises an aqueous solution of ethanol, and organic compound, a polar aprotic solvent, ethanedial and bisphenol A.
U.S. Pat. No. 5,948,397 discloses skin care treatment for embalmed bodies. The goal of the composition disclosed in this patent is to prevent skin protein denaturing and desiccation of skin due to the process of embalming.
Aldehydes other than formaldehyde, especially glutaraldehyde have also found use in embalming. However, at least some of the above problems have also occurred here.
Accordingly, this invention aims to provide an essentially aldehyde-free embalming fluid that is non-toxic, easy to make up and use, effective, and which is also environmentally acceptable and biodegradable.